From fe8bcda64e4d30cf91f2807973940873c1a577a2 Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime@cerno.tech>
Date: Mon, 11 Jan 2021 15:23:04 +0100
Subject: [PATCH] drm/vc4: hdmi: Support BCM2711 CEC interrupt setup

The HDMI controller found in the BCM2711 has an external interrupt
controller for the CEC and hotplug interrupt shared between the two
instances.

Let's add a variant flag to register a single interrupt handler and
deals with the interrupt handler setup, or two interrupt handlers
relying on an external irqchip.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
---
 drivers/gpu/drm/vc4/vc4_hdmi.c | 42 ++++++++++++++++++++++++++--------
 drivers/gpu/drm/vc4/vc4_hdmi.h |  7 ++++++
 2 files changed, 39 insertions(+), 10 deletions(-)

--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -1725,9 +1725,11 @@ static int vc4_hdmi_cec_adap_enable(stru
 			   ((3600 / usecs) << VC4_HDMI_CEC_CNT_TO_3600_US_SHIFT) |
 			   ((3500 / usecs) << VC4_HDMI_CEC_CNT_TO_3500_US_SHIFT));
 
-		HDMI_WRITE(HDMI_CEC_CPU_MASK_CLEAR, VC4_HDMI_CPU_CEC);
+		if (!vc4_hdmi->variant->external_irq_controller)
+			HDMI_WRITE(HDMI_CEC_CPU_MASK_CLEAR, VC4_HDMI_CPU_CEC);
 	} else {
-		HDMI_WRITE(HDMI_CEC_CPU_MASK_SET, VC4_HDMI_CPU_CEC);
+		if (!vc4_hdmi->variant->external_irq_controller)
+			HDMI_WRITE(HDMI_CEC_CPU_MASK_SET, VC4_HDMI_CPU_CEC);
 		HDMI_WRITE(HDMI_CEC_CNTRL_5, val |
 			   VC4_HDMI_CEC_TX_SW_RESET | VC4_HDMI_CEC_RX_SW_RESET);
 	}
@@ -1799,8 +1801,6 @@ static int vc4_hdmi_cec_init(struct vc4_
 	cec_fill_conn_info_from_drm(&conn_info, &vc4_hdmi->connector);
 	cec_s_conn_info(vc4_hdmi->cec_adap, &conn_info);
 
-	HDMI_WRITE(HDMI_CEC_CPU_MASK_SET, 0xffffffff);
-
 	value = HDMI_READ(HDMI_CEC_CNTRL_1);
 	/* Set the logical address to Unregistered */
 	value |= VC4_HDMI_CEC_ADDR_MASK;
@@ -1808,12 +1808,32 @@ static int vc4_hdmi_cec_init(struct vc4_
 
 	vc4_hdmi_cec_update_clk_div(vc4_hdmi);
 
-	ret = devm_request_threaded_irq(&pdev->dev, platform_get_irq(pdev, 0),
-					vc4_cec_irq_handler,
-					vc4_cec_irq_handler_thread, 0,
-					"vc4 hdmi cec", vc4_hdmi);
-	if (ret)
-		goto err_delete_cec_adap;
+	if (vc4_hdmi->variant->external_irq_controller) {
+		ret = devm_request_threaded_irq(&pdev->dev,
+						platform_get_irq_byname(pdev, "cec-rx"),
+						vc4_cec_irq_handler_rx_bare,
+						vc4_cec_irq_handler_rx_thread, 0,
+						"vc4 hdmi cec rx", vc4_hdmi);
+		if (ret)
+			goto err_delete_cec_adap;
+
+		ret = devm_request_threaded_irq(&pdev->dev,
+						platform_get_irq_byname(pdev, "cec-tx"),
+						vc4_cec_irq_handler_tx_bare,
+						vc4_cec_irq_handler_tx_thread, 0,
+						"vc4 hdmi cec tx", vc4_hdmi);
+		if (ret)
+			goto err_delete_cec_adap;
+	} else {
+		HDMI_WRITE(HDMI_CEC_CPU_MASK_SET, 0xffffffff);
+
+		ret = devm_request_threaded_irq(&pdev->dev, platform_get_irq(pdev, 0),
+						vc4_cec_irq_handler,
+						vc4_cec_irq_handler_thread, 0,
+						"vc4 hdmi cec", vc4_hdmi);
+		if (ret)
+			goto err_delete_cec_adap;
+	}
 
 	ret = cec_register_adapter(vc4_hdmi->cec_adap, &pdev->dev);
 	if (ret < 0)
@@ -2288,6 +2308,7 @@ static const struct vc4_hdmi_variant bcm
 		PHY_LANE_CK,
 	},
 	.unsupported_odd_h_timings	= true,
+	.external_irq_controller	= true,
 
 	.init_resources		= vc5_hdmi_init_resources,
 	.csc_setup		= vc5_hdmi_csc_setup,
@@ -2314,6 +2335,7 @@ static const struct vc4_hdmi_variant bcm
 		PHY_LANE_2,
 	},
 	.unsupported_odd_h_timings	= true,
+	.external_irq_controller	= true,
 
 	.init_resources		= vc5_hdmi_init_resources,
 	.csc_setup		= vc5_hdmi_csc_setup,
--- a/drivers/gpu/drm/vc4/vc4_hdmi.h
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.h
@@ -61,6 +61,13 @@ struct vc4_hdmi_variant {
 	/* The BCM2711 cannot deal with odd horizontal pixel timings */
 	bool unsupported_odd_h_timings;
 
+	/*
+	 * The BCM2711 CEC/hotplug IRQ controller is shared between the
+	 * two HDMI controllers, and we have a proper irqchip driver for
+	 * it.
+	 */
+	bool external_irq_controller;
+
 	/* Callback to get the resources (memory region, interrupts,
 	 * clocks, etc) for that variant.
 	 */
